Add 80/21 and 98/12, Solve 3 17/21 + 8 2/12 as a fraction

Add 80/21 and 98/12

1^st number: 3 17/21, 2^nd number: 8 2/12

80/21 + 98/12 is 503/42.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
80/21 = 80 × 4/21 × 4 = 320/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
98/12 = 98 × 7/12 × 7 = 686/84
Add the two like fractions:
320/84 + 686/84 = 320 + 686/84 = 1006/84
1006/84 simplified gives 503/42
So, 80/21 + 98/12 = 503/42
In mixed form: 1141/42

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